Separable electrical connector



Feb. 1, 1955 E. M. SORENG SEPARABLE ELECTRICAL CONNECTOR Filed Oct. 18, 1952 Ed 51' ME'nrang United States Patent SEPARABLE ELECTRICAL CONNECTOR Edgar M. Soreng, Glenview, 11]., assignor, by mesne assignments, to Soreng Products Corporation, a corporation of Delaware Application October 18, 1952, Serial No. 315,524

3 Claims. (Cl. 339-256) This invention relates to separable electrical connectors of the type comprising cooperating male and female elements and wherein insertion of a blade-like male element into the socket of a female element effects a good electrical connection between conductors attached to said elements.

In general it is the object of this invention to provide improved electrical connecting means of the character described.

More particularly it is an object of this invention to provide a female element for electrical connecting means of the character described which is capable of receiving the blade portions of male connectors having any of a wide range of thicknesses and of making a good electrical and mechanically secure connection with them.

A further object of the invention is to provide an improved manner of clinching a ferrule portion on one of the connector elements onto the bared end of a wire conductor inserted into said ferrule portion.

With the above and other objects in view, which will appear as the description proceeds, this invention resides in the novel method and apparatus hereinafter described and more particularly defined by the appended claims, it being understood that such changes in the precise embodiment of the hereindisclosed invention may be made as come within the scope of the claims.

The accompanying drawing illustrates several complete examples of the physical embodiment of the invention constructed according to the best modes so far devised for the practical application of the principles thereof, and in which:

Figure l is a perspective view of the female element of the electrical connecting means of this invention, having a wire conductor clinched thereonto;

Figure 2 is a perspective view of the male element of the electrical connecting means of this invention;

Figure 3 is a side elevational view showing the blade portion of the male element in the socket of the female element, portions of both elements being broken away and shown in section;

Figure 3a is a fragmentary view similar to Figure 3 but showing a modification of the female element of that figure;

Figure 4 is a bottom view of the female element shown in Figure 1;

Figure 5 is an enlarged fragmentary sectional view taken through Figure 2 along the plane of line 5-5;

Figure 6 is a perspective view similar to Figure l but illustrating a modification of the female element;

Figure 7 is a perspective view similar to Figure 2 but illustrating another form of male element;

Figure 8 is a view similar to Figure 3 showing the connector elements of Figures 6 and 7 connected together;

Figure 9 is a view similar to Figure 4 but illustrating another modification of the female element; and

Figure 10 is a sectional view taken through Figure 9 on the plane of the line 1010.

Referring now particularly to the accompanying drawing in which like reference characters designate like parts throughout the several views, the electrical connecting means of this invention comprises a female element generally designated 5 and a male element generally designated 6. These elements are connectable to gether as indicated in Figure 3 to establish a good electrical connection between an electrical conductor 7 attached to the female element and an electrical instrumentality (not shown) upon which the male element "ice maeiy be mounted and of which it may comprise a termin The male element 6 has a relatively flat mounting portion or base 9 provided with an aperture 10 to receive a rivet or similar securement means (not shown) by which the male element may be mounted on the terminal head, for instance, of an electrical instrumentality such as a switch or the like. The rivet, of course, may thus serve to electrically connect the male element of the connector with one of the contacts of the switch.

Integral with the mounting portion or base 9 of the male element and extending forwardly therefrom is a flat elongated blade 12, which is preferably disposed at an obtuse angle to the base 9. At its front end the blade is chamfered as at 13 to facilitate its insertion into the socket 14 of the female element.

Near to, but spaced from, the junction of the blade 12 with the mounting portion or base 9, the blade portion has a pair of opposite lateral protuberances 15 which are swedged or pressed out of the body of the blade as a consequence of the formation of indentations 16 in its upper face, one near each longitudinal side edge of the blade. The lateral protuberances provide stop abutments on the opposite side edges of the blade which are engageable with the front of the female element 5 of the connector means to limit the extent to which the blade,12 may be inserted into the socket 14 of the female element.

It is noteworthy that formation of the stop abutments 15 by displacing edge portions of the blade laterally permits the male element to be formed of strip stock, thus avoiding waste of material in its manufacture, as would be the case if the male element were stamped from sheet stock to the outline shown.

The blade portion 12 of the male element is provided with a pair of relatively shallow indentations 18, one in each of its faces, located substantially medially between the opposite side edges of the blade and substantially medially between its chamfered front end 13 and the stop abutments 16 on its side edges. These indentations, which provide detent wells cooperable with a detent protuberance on the female member, to be described later, are disposed directly opposite one another and have arcuate bottoms concentric to an axis which extends crosswise of the blade 12.

The female element of the connector is preferably formed from sheet metal as a unitary stamping and comprises generally the socket 14 at its front in which the blade of the male element is adapted to be received and a ferrule portion 21 behind the socket and which may be clinched to a bared end portion of a wire conductor to secure the female element thereto with a good me chanical and electrical connection.

The socket of the female element comprises an elongated substantially flat base 23 and a pair of opposite flaps 24 folded toward one another over the upper face of the base to lie in spaced substantially parallel relation to the base with their adjacent longitudinal edge portions overlying the medial portion of the base. More specifically, each of the flaps 24 has its medial portion cut away so that it comprises a flange 25 which extends upwardly along the longitudinal side edge of the base, a pair of tabs 26 extending inwardly across the base and parallel thereto from the upper edge of the flange at the end portions thereof, and a finger 27 connecting the pair of tabs at their inner end portions so as to extend longitudinally between them. The fingers 27 are bowed downwardly at their medial portions so that their undersides at these portions are spaced from the upper surface of the base a distance slightly less than the thickness of the blade of a male element; and it will be seen that these fingers are free to flex along their lengths so that they will exert a substantial clamping force upon the blade of a male element which has been inserted into the socket to thus urge the blade into firm contacting engagement with the base. It will also be apparent that because of their downwardly bowed shape these fingers can readily be cammed upwardly by the chamfered front end of the male element blade as the same is inserted into the socket, and that the socket can therefore accommodate male element blades of a wide range of thicknesses.

If desired, the fingers may be given an undulating form, as at 27 (Figure 3112), at each end of their downwardly bowed central positions, and the metal of which they are composed will then be stretched and thinned to accommodate the extra length of the undulations, thus providing a somewhat easier spring action.

The base of the female member has a pair of parallel, spaced apart transverse slots 29 which extend most of the distance across it, and these slots define between them a strip 30 which is integral with the base but the medial portion of which is capable of upward and downward flexing with respect to the remainder of the base. Obviously this strip could be given an undulating form, like that of the fingers 27', either instead of or in addition to the undulated fingers. A medial protuberance or nub 32 on this strip extends up into the socket, towards the fingers 27, and in the fully inserted position of the blade into the socket engages with a detent action in one of the detent wells 18 in the blade portion of the male element to thus preclude accidental withdrawal of the male element from the female member, maintaining a good mechanical connection between these units. The detent is of course activated by the resilience of the strip 39. together with the spring fingers 27 which yieldingly urge the blade of the male element down onto the nub 32. It will be noted in this respect that both faces of the blade of the male element are provided with detent wells 18 in order to permit the blade to be inserted into the socket of the female element with either of its faces uppermost. It is also noteworthy that the detent wells 18 are formed by a coining operation which in effect compresses the portion of the blade lying between the bottoms of the indentations, and the rounded configuration of the bottoms of the indentations leaves, at the longitudinal extremities of the indentations, only a suggestion of a corner which is not sharp enough to catch upon the detent protuberance of the female element and thus interfere with withdrawal of the blade portion from the sec et.

Where the blade of the male element is provided with abutment protuberauces 16, these of course engage against the front edge of the flanges 25 on the female member to define the fully inserted position of the blade into the socket, and they are located at a distance to the rear of the centerline of the detent wells 18 such that the detent is engaged when the protuberances abut the flanges on the sockets. To render the female connector of this invention adaptable for use with male elements which do not have such protuberances, the base of the female element is provided, near the rear of the socket, with a forwardly facing shoulder or abutment 34 comprising the free edge of a tang 35 struck upwardly out of the surface of the base, which abutment is engaged by the front edge of the blade when the male element is fully seated in the socket.

Instead of the dimple and pimple detent arrangement described above, another type of detent, illustrated in Figures 6, 7 and 8, may be employed on the connector elements of this invention. In this instance the female element is provided with a small tongue 37 which projects forwardly and upwardly at an obtuse angle from the front edge of the base and which engages behind a rearwardly facing ledge 38 at the rear of the blade. This ledge is defined by a medial aperture 39 in the male element at the iunction of the blade and body portions thereof. Preferably, as seen in Figure 8, the tongue engages behind the ledge at the point in the insertion of the blade into the socket when the front edge of the blade is engaged by the abutment 34, and the detent action will result from engagement of the tongue behind the ledge. it will be observed that the connector elements embodyin this detent arrangement will be assembled with the blade at a slight downward angle with respect to the socket upon its initial insertion into the socket. and that the chamfer at the leading edge of the blade will enable the blade to cam its way between the upstanding tongue and the downwardly bowed medial portions of the fingers 27. The fingers, by their flexing. will of course provide the spring reaction by which the detent is activated. Obviously, where the connector elements are provided with the type of detent arrangement just described it is not necessary that the male element have the lateral protuberances or stop abutments 15. It will also be obvious that although detent wells 18 are not required in the blade of the male element with the detent arrangement just described, they may nevertheless be provided to render the male connector adaptable for interchangeable use with female connector elements like that shown in Figure 4.

The socket portion of the female element may also be modified in another manner as illustrated in Figure 9 wherein the slots 29 are disposed longitudinally, ad jacent to the side edges of the base, and the tang 35 is substantially triangular and is bent upwardly at right angles to the base to provide a forwardly facing shoulder 34 corresponding in function and purpose to the shoulder 34 of the Figures 3 and 4 embodiment. Because of the triangular cut-out at the rear of the base, left by bending the tang 35 up out of the base, the strip 30 which carries the detent nub 32 is substantially Y-shaped. In this embodiment also, as best seen in Figure 10, the flaps 24 do not have the medial cut-outs which define the tabs and fingers described in connection with the Figure l embodiment, but instead the flaps have their adjacent longitudinal edges curved slightly downwardly, and, the flaps being naturally somewhat resilient, they cooperate with the strip 30' in securely clamping the blade of the male element.

The ferrule portion 21 of the female element, at the rear thereof, is integral with the socket portion and comprises two pairs of prongs 42 and 43, respectively, which in their unbent condition comprise pairs of opposite lateral projections on the blank from which the female element is formed. The front pair of prongs 42 are clinched around the bare end portion of a wire to provide a good electrical and mechanical connection there to, while the rear pair 43 clamp around the insulation immediately adjacent to the bared end portion of the conductor to mechanically reinforce the connection between the conductor and the connector. As viewed from the side, the portion of the base of the ferrule which lies immediately beneath the rear pair of prongs is stepped down slightly, as at 44, to accommodate the additional thickness of the insulation on the conductor and thereby dispose the insulated and bared end portions of the conductor coaxially with one another in the ferrule.

The front pair of prongs are tab-like and are curled around the bared end portion of the wire in such a way that their outer marginal edge portions are brought into upwardly projecting flatwise adjacent relationship as at 46 upon the completion of the clinching operation. Immediately below these upstanding marginal edge portions the prongs curl downwardly into the mass of wire strands of the conductor, as at 47, so as to assure that the wire will be firmly clinched by the ferrule. It will be seen that the turning upwardly of the adjacent marginal edge portions of the prongs 42 not only facilitates the clinching operation but also enables the prongs to be more tightly wrapped around the wire so that the ferrule on the female element of the connector of this invention has an unusually good electrical and mechanical connection with the conductor to which it is secured.

From the foregoing description taken together with the accompanying drawing it will be apparent that this invention provides improved electrical connecting means of the type comprising cooperating male and female elements and wherein insertion of a blade-like male element into the socket of the female element effects a good electrical and mechanical connection between said elements; and it will also be seen that the female element of the connector of this invention is capable of accommodating the blade portions of male connectors having various thicknesses, making a good electrical and mechanical connection with them.

What I claim as my invention is:

l. separable electrical connecting means comprising: a female element having an elongated substantially fiat base at one end portion thereof; means on the base cooperating therewith to provide a relatively flat socket opening to said end of the female element, said means comprising parallel flanges extending a short distance upwardly from the longitudinal margins of the base, a pair of tabs extending inwardly over the base from the opposite end portions of each flange to flatwise overlie the base in spaced substantially parallel relation thereto, and a finger extending longitudinally between the tabs of each pair thereof and integrally joined thereto, said fingers being spaced from the flanges and closely adjacent to one another and overlying the medial portion of the base and being bowed inwardly toward the base; a male element having an elongated relatively flat blade portion at one end to fit said socket and insertable endwise into said open end thereof to be confined fiatwise between the base of the female element and said fingers, said blade portion having a thickness slightly greater than the spacing between the base and the undersides of said fingers so that the latter are forced upwardly away from the base by insertion of the blade portion into the socket and exert a substantial clamping force on the blade portion tending to resist withdrawal thereof from the socket and assuring good electrical contact between the male and female elements; and cooperating detent means on the base of the female element and the blade portion of the male element, releasably held in firm engagement by the clamping force of the fingers on the blade portion to assist the fingers on the blade portion in resisting withdrawal of the blade portion from the socket, said detent means comprising a flatwise yieldable strip on the base having its ends integrally joined thereto, said strip being defined by spaced substantially parallel slits in the base extending lengthwise between the junctions of the flanges with the base, and a rounded nub on the medial portion of said strip cooperable with wells in the opposite faces of the blade portion, either of which wells is adapted to receive said nub depending upon which face of the blade portion is disposed adjacent to the base of the socket when the blade portion is inserted thereinto.

2. A female electrical connector element of the character described comprising: a substantially channelshaped base having a web-like bottom and a pair of upwardly extending flanges along its sides; a pair of spaced apart tabs integral with and extending inwardly from each of the flanges on the base and overlying the bottom of the base substantially parallel thereto; a finger extending longitudinally between the tabs of each pair thereof and integrally joined thereto, said fingers being spaced inwardly from the flanges and overlying the central portion of the bottom of the base, closely adjacent to one another, and being bowed downwardly; an elongated detent strip integral with the base and defined by a pair of spaced apart substantially parallel slots and having a medial portion directly beneath and yieldingly flexible toward and from the undersides of said fingers at a zone substantially midway between the ends of the fingers; and a nub on said medial portion of the strip extending upwardly therefrom and adapted to cooperate with a recess in a face of a male connector blade element to define a detent which is activated in consequence of the resilience of said strip while the remainder of said face of the male connector blade element is pressed into firm flatwise engagement with the remainder of the bottom of the female element base by pressure of said fingers upon the opposite face of the male element.

3. The connector of claim 2, further characterized by the fact that said fingers have sections on each side of downwardly bowed portions thereof which undulate toward and from the base, so that the metal of the fingers is thinner, especially at their downwardly bowed central portions, in consequence of the stretching required 11:10 produce the undulations, than in the remainder of the aps.

References Cited in the file of this patent UNITED STATES PATENTS 2,503,559 Miloche Apr. 11, 1950 2,550,636 Bergan Apr. 24, 1951 2,552,392 Bateheller May 8, 1951 2,579,739 Hayes Dec. 25, 1951 2,600,190 Batcheller June 10, 1952 

